The main aim of the research project is an understanding of the chemical reactivity of flavin coenzymes and how this reactivity is used and controlled in biological systems. The methods of approach will be the study of specific enzymes representative of the various classes of flavoproteins and studies of model systems. Considerable use will be made of steady state kinetics coupled with rapid reaction kinetic studies, and of the technique of replacing the natural coenzymes of falvoproteins with synthetic flavins, in order to test hypothetical schemes and to probe the nature of the environment immediately around the flavin. The latter is particularly important in providing information about the active site region in proteins where the structure is not available from X-ray crystallography. We also plan to undertake the amino acid sequence of L-lactate oxidase in order to aid in the crystallographic determination of its three-dimensional structure.